diff --git a/arch/x86/cpu.c b/arch/x86/cpu.c
index b5aad5e52..e0a739846 100644
--- a/arch/x86/cpu.c
+++ b/arch/x86/cpu.c
@@ -59,6 +59,9 @@ int phy_cpu_num;
 unsigned long pcpu_sync = 0;
 uint32_t up_count = 0;
 
+/* physical cpu active bitmap, support up to 64 cpus */
+uint64_t pcpu_active_bitmap = 0;
+
 DEFINE_CPU_DATA(uint8_t[STACK_SIZE], stack) __aligned(16);
 DEFINE_CPU_DATA(uint8_t, lapic_id);
 DEFINE_CPU_DATA(void *, vcpu);
@@ -392,6 +395,8 @@ void bsp_boot_init(void)
 		VMX_MACHINE_T_GUEST_SPEC_CTRL_OFFSET,
 		"run_context ia32_spec_ctrl offset not match");
 
+	bitmap_set(CPU_BOOT_ID, &pcpu_active_bitmap);
+
 	/* Get CPU capabilities thru CPUID, including the physical address bit
 	 * limit which is required for initializing paging.
 	 */
@@ -535,6 +540,8 @@ void cpu_secondary_init(void)
 			      (get_cur_lapic_id()),
 			      CPU_STATE_INITIALIZING);
 
+	bitmap_set(get_cpu_id(), &pcpu_active_bitmap);
+
 	/* Switch to run-time stack */
 	CPU_SP_WRITE(&get_cpu_var(stack)[STACK_SIZE - 1]);
 
@@ -646,6 +653,8 @@ void cpu_halt(uint32_t logical_id)
 	/* Set state to show CPU is halted */
 	cpu_set_current_state(logical_id, CPU_STATE_HALTED);
 
+	bitmap_clr(get_cpu_id(), &pcpu_active_bitmap);
+
 	/* Halt the CPU */
 	do {
 		asm volatile ("hlt");
diff --git a/include/arch/x86/cpu.h b/include/arch/x86/cpu.h
index 9bd305fa9..6a3085932 100644
--- a/include/arch/x86/cpu.h
+++ b/include/arch/x86/cpu.h
@@ -198,6 +198,7 @@ EXTERN_CPU_DATA(uint8_t[STACK_SIZE], stack) __aligned(16);
 
 extern void *per_cpu_data_base_ptr;
 extern int phy_cpu_num;
+extern uint64_t pcpu_active_bitmap;
 
 #define	PER_CPU_DATA_OFFSET(sym_addr)					\
 	((uint64_t)(sym_addr) - (uint64_t)(_ld_cpu_data_start))